Burglar-alarm



(No Model.) 2 Sheets-Sheet 1.

' J. ISRAEL.

BURGLAR ALARM.

No.- 386,188. Patented July 17, 1888.

mu m

IJJIHTTUWH NTOR J2) .ZZsraeZ, By 7112? flttorn (No Model.) I

2 Sheets-Sheet 2.. J. ISRAEL.

BURGLAR A LARM No. 386,133. Patented July 17, 1888.

, /z/g-Z.

NTOR. t John "ael,

UNITED STATES PATENT OFFICE.

JOHN ISRAEL, OF ST. LOUIS, MISSOURI.

BURGLAR-ALARM.

SPECIFICATION forming part of Letters Patent No. 386,133, dated July 17,1888.

Application filed February 2, 1988. Serial No. 262,794.

To aZZ whom, it may concern.-

Be it known that I, JOHN ISRAEL, of St. Louis, in the State of Missouri, have invented certain new and useful Improvements in Burg larAlarm Mechanism, of which the following is a specification, reference being had to the accompanyingdrawings.

My invention relates to that class of detonating burglar-alarms shown in my United States Patents Nos. 193,002 and 224,017.

The object of my present improvements is to provide a burglaralarm which can be readily attached to the inside of a door, and then can be adjusted in the firing position by means of a key from the outside of the door, so that when the door is attempted to be opened the alarm will be fired.

In the accompanying drawings, illustrating my improvements, Figure 1 is a longitudinal section, partly in elevation, of my firing-cylinder in position for firing applied to a door which opens outwardly. Fig. 2 is another view of my firing-cylinder applied to a door which opens inwardly, showing a modified form of connecting it to the door, and showing the stop which is necessary to be used where the door opensinwardly. Fig. 3 is a plan view of the device shown in Fig. 2, the dotted lines indicating it turned out of the firing position; and Fig. at is another modified form of means of connecting the firing mechanism to a door.

A indicates a firing-cylinder; B, a spring plunger; 0, a slot for the fulminate; D, ahollow projection for the escape of the gas, and E a shank for attaching the firing-cylinder. All these parts are substantially similar to the firing-alarm mechanism shown in my said patents.

My present improvements consist in means, which I will now describe, for applying such a firing mechanism adjustably upon the inside of a door, so that it may be operated by a key from the outside after the door is closed to adjust it to such position that it will be fired in case of an attempt to open the door.

F indicates a bed-plate, and G a circular base-plate attached to the shank of the firingcylinder.

H indicates clips or holders for securing the base-plate in position to rotate upon the bedplate.

(No model.)

I indicates an opening in the shank for the key K.

Referring to Fig.1,whichshowsthedevice applied upon a door opening outwardly, it will be seen that all that is necessary to make it operate is to set the plunger by means of its holdingnotch X in the firing position, then close the door, apply the key, and turn the firing-cylinder a quarter of a revolution to a horizontal position. Then when the door is attempted to be opened the outer end of the plunger will strike the door-jamb, release it, and lire the fulminate Z.

In case it is desired to apply the firing-alarm to a door opening inwardlyas, for example, an ordinary front door of the dwellingI provide a catch, L, Fig. 2, on the door-jamb U. which will release the spring plunger and cause an explosion whenever the door T is opened inwardly, the firing-alarm being operated by the key from the outside of a door, as before described, to adjust it into the firing.

Any suitable form of key may used, and any suitablemeans of applying the firing mechanism to the inside of a door, so that it will turn a quarter of a revolution, may be employed without departing from the substance of my invention.

In Fig. 2 I show clampscrews M. In Fig. 4 I show a curved angle-bar, N, which admits of very readily attaching and detaching the base-plate of the shank of the firing mechan- 18111.

\Vhat I claim to be new, and desire to soon re by Letters Patent of the United States, is-

In a detonating lmrglar-alarm, the combination of a firing-cylinder and its firing mechanism, a shank for the cylinder provided with a key-hole, a key to rotate the shank-cylinder and firing mechanism, a base-plate for the shank, and means for holding the base-plate to place upon the inside of a door, so that the 'key will operate from the outside, substantially as set forth.

In testimony whereof I have hereunto subscribed my name.

JOHN ISRAEL.

\Vitnesses:

Martens S. HOPKINS, G. l ELwELL. 

